Prevent combinations of options such as --all with --include

Previously such nonsensical combinations always treated the matching option
as if it didn't match.

For now, made find --branch refuse matching options that need a
filename, because one is not provided to them in a way they'll use.
There's an open bug report to support it, but making it error out is
better than the old behavior of not finding what it was asked to.

Also, made --mimetype combined with eg --all work, by looking at the
object file when operating on keys.

Limit.hs

@@ -159,14 +159,16 @@ matchMagic
 matchMagic _limitname querymagic selectprovidedinfo selectuserprovidedinfo (Just magic) glob = 
 	Right $ MatchFiles
 		{ matchAction = const go
-		, matchNeedsFileName = True
+		, matchNeedsFileName = False
 		, matchNeedsFileContent = True
 		, matchNeedsKey = False
 		, matchNeedsLocationLog = False
 		}
   where
  	cglob = compileGlob glob CaseSensative (GlobFilePath False) -- memoized
-	go (MatchingKey _ _) = pure False
+	go (MatchingKey k _) = withObjectLoc k $ \obj -> 
+		maybe False (matchGlob cglob)
+			<$> querymagic magic (fromRawFilePath obj)
 	go (MatchingFile fi) = case contentFile fi of
 		Just f -> catchBoolIO $
 			maybe False (matchGlob cglob)